| 摘要 |
PROBLEM TO BE SOLVED: To provide a mold for vulcanization in which a pneumatic tire provided with a land part provided with recessed parts such as channels, syps and holes, to be exposed after wearing in some extent which have been hardly manufactured before can be molded. SOLUTION: Two blade holding gears 86 each fitted with a circular arc- shaped blade 90 are rotatably combined with each other in the opposite direction on the outer periphery of the top mold and the bottom mold 14. Gears 88 formed on the outer peripheral sides of the blade holding gears 86 are made to mesh racks 98 movable by means of a cylinder. Vulcanization of a green tire is performed under a condition where apexes of two blades 90 are brought into contact with each other in the recessed part 22 for forming a land part and after the vulcanization is finished, the racks 98 are moved in the opposite directions each other to pull out the blades 90 from the recessed part 22 for forming the land part. A syp extending in a circular arc-shape which is not exposed on the tread face when it is new but is exposed after wearing, is formed. |
